In the manufacturing of metal cans out of aluminum or steel sheets or the like, it is a common practice to coat one surface of the sheet with a paint-like coating before cutting and processing the sheet into can sizes and shapes. Usually such coating is applied by means of a large coating roller which is about 15" in diameter and to 4' in length. Usually the outer surface of the cylinder is covered with a resilient, plastic layer that operates as the coating applying surface.
Coating rollers of the above described and similar types are usually made by first forming a metal cylindrically shaped drum and then casting or molding a plastic layer upon the surface of the drum. The plastic layer must be of uniform thickness and concentricity relative to the drum surface and axis in order to assure uniformity of coating. Thus, it must be carefully applied, properly sized and when worn, must be replaced or reconstructed.
Thus, efforts have been made to utilize a replaceable covering, sometimes called a "blanket" which can be replaced, when worn, with a fresh covering. This sort of replaceable covering is found in rollers used for other purposes, but which have a similar structure to rollers used for applying coatings upon metal sheet.
In order to assure continuous production in an manufacturing facility, it is desirable to be able to exchange the surface of the roller with a fresh surface by removing and replacing the coating or "blanket" rapidly and in a manner which assures uniformity of diameter and concentricity.
Rollers utilizing bonded surfaces must be replaced in their entirety with a fresh roller and the old roller must be cleaned and re-coated so that a considerable amount of time is required for this purpose. Most importantly, a production line might have to be shut down for some while in order to remove and replace a complete roller.
Efforts to use a separate blanket or coating on rollers involved systems for applying and fastening the covers to the rollers which were not accurate and were relatively expensive. In addition, if a replaceable cover is to be used in an existing manufacturing facility, such as in a mill where sheet steel or sheet aluminum is being processed for aluminum cans, it is desirable to utilize the already existing rollers available because of the substantial expense involved in replacing rollers.
Hence, the invention herein is concerned with an improved manner for covering a coating roller with a removable blanket or cover wherein an existing roller can be utilized and can be modified by relatively inexpensive additions for use in receiving and supporting a removable cover. This construction also is useful for other rollers, such as lithographic types of rollers, die cutting back-up rollers and the like.